1. Field of the Invention
Exemplary embodiments of the present invention relate to a separated target apparatus used as a deposition source in a sputtering operation, and a sputtering method using the separated target apparatus.
2. Discussion of the Background
In general, a thin film transistor (TFT) that is applied to a display apparatus is manufactured via a deposition process such as magnetron sputtering. That is, sputtering is performed on a deposition target so that a thin film having a desired pattern is formed on a substrate of the display apparatus which is a deposition target object.
However, as a size of a screen of the display apparatus increases, it becomes difficult to manufacture the deposition target so as to allow the deposition target to have the same size as the screen. That is, the TFT is completely formed on the screen of the display apparatus, and in this regard, a significant load is caused in manufacturing and handling the deposition target so as to allow the deposition target to have almost the same size as the screen. Also, as the use of a TFT whose active layer is formed of oxide increases, an oxide target may be more frequently used during sputtering. However, the oxide is fragile such that it is difficult to manufacture and to handle the oxide when the oxide is large.
Recently, in consideration of these problems, a separated target apparatus may be used, and in the separated target apparatus, a deposition target may be formed of a plurality of small separated targets that are easily manufactured and handled, and then adhered to a base plate. Afterward, during sputtering, the separated target apparatus performs a deposition operation while the target assembly of the separated target apparatus moves along a screen. That is, the deposition target is not formed to have a size capable of completely covering a screen but is formed by connecting small separated targets, and a size of the connected small separated targets covers only a portion of the screen. Afterward, during sputtering, the separated target apparatus performs the deposition operation while the deposition target of the separated target apparatus moves along a screen.
However, since the deposition target may be formed of a plurality of small separated targets, a quality deviation between an area corresponding to a gap between the small separated targets, and an area corresponding to an inner portion of each separated target may increase. That is, since end corners of each separated target are positioned adjacent to the area corresponding to the gap between the small separated targets, a voltage value and a magnetic field value in the gap are greater than those values in the inner portion, so that a deposition quality may become irregular.
Due to the aforementioned problems, brightness on a screen of a display apparatus that is a final product may not be uniform, and a level of a brightness deviation may increase in portion to the size of the screen.
Thus, there is a demand for a solution capable of solving these problems.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form any part of the prior art nor what the prior art may suggest to a person of ordinary skill in the art.